Multiple telephony upon one and the same electromagnetic wave



Jan. 8, 1929. 1,697,941

W. VON GLOWACKI MULTIPLE TELEPHONY UPON ONE 4AND THE SAME ELEOTROMAGNETIC wAvE Warum/2.5515? 22mg@ Tra/577% i fi JNVENTOR. v Pew-.fer #I'l' wLAmMm von awww/ 1 Y l l V B Ogm /m/M ATTORNEYy Patented Jan. 8, 1929.

UNITED STATES PATENT OFFICE.

wLAnmrn voNiGLOWAcxI, or KOLOMEA, POLAND, A'ssIGNOR To RADIO CORPORATION OF AMERICA, A CORPORATION OF DELAWARE,

MULTIPLE TELEPHONY UPON' ONE AND THE SAME ELECTROMAGNETIC WAVE.

Application led August 6, 1926, Serial Nol 127,588, and in Austria January 12, 1926.

The subject matter of the present inven-` electromagnetic wave. The purpose 'aimedA at is attained, according to the invention, by

connecting the telephone apparatus, through light sensitive conductors subject to synchronous iniuence or control so that they are in regular'alternation or sequence with one another.

In the drawing I have shown two of the many embodiments of my invention, in which Fig. 1 shows a preferred form using a rotating drum provided with a reiecting means for directing the light bearnf; and

Fig. 2 shows a modified form of control which comprises a reiecting means operating with a tuning fork and periodic interrupter. k

Referring first to the embodiment disclosed by Fig. 1 of the accompanying drawing', the arrangement is enclosed in anopaque box 1 in which, upon a revoluble shaft or spin-l dle 2, a drum 3 made of some convenient material, preferably filled with a little mercury, is disposed. Upon this drum 3, at equal distances from one another, there are arranged very thin and narrow soft-iron rods 4. Immediately below the drum 3' is arranged a conveniently formed electromagnet 5 which conjointly with the tuning-fork interruptor 6 is inserted in the direct current source circuit 7. Upon the drum 3 Is provided a reflecting surface 8 having a mirror-like polish, and into this surface 8 are cut reflecting notches 9 in close proximity to one another and being so' cut that the angles of inclination thereof with reference to shaft 2 are successively diferent. 10 denotes a constant light source `whose luminous beam or pencil 11 is allowed to fall through a slit in chamber 12 upon the polished reecting surface 8, being there reflected according to the angle of incidence, in the direction of photo-electric cells 13a, 13", 13C, 13d, if provided. Each of these photo-electric cells is inserted in the primary or'the secondary circuit of the corresponding microphones (142, 14", 14C, and 14d). These microphones, finally, are connected in parallel with the transmitter equipment according to wellknown methods, as, for example, in accordance with the arrangement disclosed in the drawings, wherein the separate microphones or telephones (depending upon whether la transmitting or receiving station is represented) are connected each with a separate photo-cell and parallelly connected to a transmitting or receiving system of lany desired or suitable character.

The receiving equipment is perfectly identical with the sending equipment, but in lieu of thew microphones suitable telephone receivers are provided.

The method of operation of the arrangement shown in Fig. 1 is'as follows:y

After the tuning-fork interrupters of the sending and receiving stations have been carefully tuned to the same pitch, the drum 3 in the transmitter or receiver apparatus and the identically built drum in the receiving apparatus revolve at the very same rate of speed in clockwise direction. The pencil of light `,rays 11 then impinging vertically upon the reflecting surface 8 both in the transmitter as well as in the receiver is delected in convenient manner by notches 9 towards the photo-electric 'or selenium cells 133, 13", 13a, 13d, mounted within box 1, whereby these are illuminated in rapid succession.

On account of such synchronous illumination of the photo-electric cells at the sending and the receiving apparatus. on the one hand, the microphones 14a, 14h, 14C, 14d are connected transiently with the transmitter 'ber of telephone apparatus provided,7 it is possible to carry on'sev'eral conversations or the like upon one and the same electromagnetic Wave simultaneously and Without any trouble. s

In Fig. 2 of the drawing is diagrammatically shown another form of construction of the above arrangement which, inserted in the y transmitter and the receiver apparatus, per- This interrupter 15 consists, in this scheme.

of an electromagnet and a keeper constructed llkea tunmg fork 16, one end of which terminates in ahghly polished and conveniently formed point 17. l()u again denotes a light source the.beam or pencil of which is caused to imping perpendicularly upon the point 17, and w ch is alternately reiected towards the photo-electric cells or selenium cells 13- 13" according to the position or oscillation of the point 17 These photo-electric cells 13, 13" are inserted in the circuits of the microphones coordinated thereto which are connected in parallel with the sending point. An identical arrangement is provided at the receivingend, with this difference that in lieu of the microphones, convenient telephone receivers, are provided. The tuning forks of the sending and receiving stations are also tuned to the identical pitch, a fact which can be readily checked by comparing the pitch of the vibrating tuning forks.

Now, the operation of this arrangement is as follows:

Due to the synchronous vibrations of the tuning forksV 16 or the highly polished points 17 in the transmitter and the receiver, the pencil of light rays issuing from luminous source l0 is alternately deflected towards the selenium cellsll, 13b, whereby the corresponding microphones of the sending point and the telephone receivers of the receiving point are transiently interconnected by wireless, Thus, in this case, twoy conversations can be carried on simultaneously without mutual interference. Accurately speaking', the conversations simultaneously carried on are interrupted in rapid succession,'with the evidentresult that fractions of the conversation are cut out; but, in the presence of a high speed of rotation of the drums, the e'ar is unable to notice the lack or loss ofthe missing fragments of the conversations.

In constructional respect a great number' of modifications are conceivable. The above outlined idea could also be utilized in connection with other arrangements than the one hereinbefore referred to.

It will be readilyv understood that an arrangement very simple'in constructional respect is dealt with, which not only allows of multiple telephony on one and the same electromagnetic wave, but which also precludes all chances of unauthorized listenmg 1n.

Having described my invention, I claim 1. An arrangement for multipletelephony upon one and the same electro-magnetic wave comprising, a transmitting and a receiving station of like characteristics, a source of light rays at each of said stations, a distributor head for directing said light located at both said transmitting and said receiving stations, a plurality of photo-electric cells located at each of said transmitting and receiving stations, and means located at both said transmitting and said receiving station for synchronously subjecting corresponding photo-electric cells at the transmitting and at the rceiving stations to the light rays directed from said distributor head of light, whereby the said synchronous operation makes and breaks the signals between coordinated apparatus at the transmitting and the receiving stations simultaneously.

2.4 Anarrangement for multiple telephony upon one and the same electro-magnetic wave comprising, a transmitting station and a re ceiving station of like characteristics, a plurality ofrphoto-electric cells located at each of said transmitting station and receivingstations, a separate microphone connected with each photo electric cell at said transmitting station and a separate telephone receiver connected with each photo-cell at said receiving station, a source of light rays at'each of said stations, a distributor head for directing said light rays positioned at each of said stations, means at each of said stations for synchronously rotating said distributor head at a speed above audibility for directing said light to corresponding photo-cells at said transmitting and said receiving stations, whereby the said reflected beams of light successively open and close a corresponding signal channel of conversation at cach station at a speed above audibility.

3. An arrangement for multiple telephony upon one and the same electro-magnetic wave comprising, a light source directing a beam of light in a predetermined direction, a refleeting means .for directing said light beam, a plurality of photo-electric cells for receiving the light beam reflected by said reliecting means, means for synchronously controlling said reflecting means so that the light beam may be successively directed from one cell to another at a predetermined rate of Speed above the range of audibility, a microphone connected with each-,fof said photo-electric cells, an energy tran'sinittiiig system, andl a connection for connectingea-ch of said cells and associated microphone in parallel with said transmitting system, whereby one speciic cell and its associated microphone is periodically and alternately connected with the ransmitting system at a fixed rate of s ee p4. An arran ement for multiple telephony luu upon one and t e same electro-magnetic wave com rising, a source of. light, a. distributor hea for directing. said llght mounted within an opaque housing, said distributor head being rotatably supported within said housing interrupting means for controlling the rotation of said distributoi` head, a plurality of reflecting means in thepath of the light rays mounted upon said distributor head, a plurality of photo-electric cells within said housing for alternately and successively receiving the light rays issuing from saidlight source as reflected by said reflecting means,

a. transmitting system, a microphone connected with each of said photo-cellsand said transmitting system foralternately and s uccessively transferring sound impulses 1mpressed thereon to said transmitting system duringthe period of time, that each respective cellis subjected to the influence of said light ray.

5. An arrangement for multiple communication upon one and the same electro-magnetic Wave which comprises, a plurality of channels for receiving sound 'Waves and converting the same into electr-ical energy, light sensitive means-for controlling vthe time of operation of sound channels,y alight source and a light beam issuing therefrom, and a rotatable means revolving at a speed above audibility for periodically and successively changing the direction of said light beam and closing a 4circuit through one of said light serlisitive means and one of said lsound channe s.

6. A system for establishinof multiple communication upon one and thb same electromagnetic wave which includes, -a transmitting station and a receiving station both of like characteristics, a plurality of microphone. channels located at said transmitting station and a plurality of telephone channels located at said receiving sta-tion, photocells located at both said stations'and associated with each microphone or telephone circuit, means located at each of said stations for alternatel' and successively sub'ecting said photo-cel s to light impulses, W ereby various microphone and telephone channels are placed in the circuit of said transmitting and receiving systems, and, means located at each of said stations for synchronously controlling the operation of said means for directing light to said photo-cells, whereby corresponding sound channels are inserted'in the transmitting and receiving systems at identically the same period of time.

7. A system for maintaining a plurality of separate communication upon one and the same electro-magnetic wave which includes,

a. transmitting station, and a receiving stat1on, each provided with a plurality of parallelly connected sound channels a source of light at each station for directing a beam 1n a predetermined path, light sensitive means associated with each of said sound channels for conducting-the separate commun ications, means for "alternatel land successively establishing a connectionl etween coordinated sound channels at said transmitting and receiving stations, said mea-ns including a light distributor for controlling said light beam and directing the same to corresponding llght sensitive means, and means located at each of said stations for synchronizingv said light distributor apparatus, whereby like channels of communication are utilized at like periods of time.

8. An arrangement for a multiple telephony upon one and the same electro-magnetic phone at the second point at said successively and periodically interrupted periods, said v-periods of interruption being above the range of audible reception, whereby interruption in the communication' between said stations is` unobservable to the ear and the accuracy of the transmitted and received message unaiected.

9. In a system for multiple communication upon' one and the same electro-magnetic wave, a transmittinor station provided with a plurality of parallelly connected sound conducting channels, a l photocell associated with each of said separate sound channels, a light source, and means provided by a plurality ofrotating mirrors for alternately,- and successively switching the light beams issuing from-said source from one photo-cell to another in a fixed order ata speed above the range of audibility, whereby sound channels associated with said photo-cells arecorrespondingly connected with said transmitting system.

v 10. An arrangement for establishing multiple telephony or the `like upon one and the same electro-magnetic wave which includes, a transmitting station, a plurality'of sound pick-up devices parallelly connected withV said transmitting station, a plurality of light sensitive photo-cells individually connected with. each of said sound sensitive means, `a light source and a rotary distributor head for successively v'directing the light rays issuing from said light sourceto separate photo-cells,

whereby the photo cells function as circuit makers and breakers for continuously and successively establishing a communication with each of said separate sound pick-up devices.

11. In a system forfmultiple communication upon one and the same electro-magnetic Wave, a source of'light and a distributor head for controlling the direction of the issuing light beam, a plurality of photo-cells alternately and successively subjected to the iny iuence of said light rays as directedfrom said distributor, a plurality of sound sensitive microphones individually connected with one of said photo-cells, and a transmitting station having each of said sound sensitive microphones parallelly connected thereto, whereby the said distributor head of light alternately and successively establishes a plurality of separate communication channels With said transmitting apparatus.

12. In a system for multiple communica- 5 tion upon one and the same electro-magnetic Wave, a transmitting system, a plurality of microphones connected in parallel therewith, a photo-cell associated with each of said mi- CERTIFICATE ,0F

Patent No. l, 697, 941.

CORRECTION.

Granted January -`1929, to

WLADIMIR von GLOWACKI. i

It is hereby certified that error appears iii the printed specification .ofv Athe above numbered patent requiring correction as follows:

Page 2, linelZ'Z, claim 4, between the syllable "ing" and the word "interrupting" insert a comma; Vand that the said Letters Patent should be4 read'with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 3rd day of December, A. D. 1929.

(Seal) M. J. Moore, Acting Commissioner of Patents. 

